Timber and the Climate Crisis

Cross-laminated timber has become, in the last decade, one of the most discussed materials in architecture. It is positioned as a climate-positive alternative to concrete and steel — a building material that stores carbon rather than emitting it, that comes from a renewable source, and that can be fabricated with precision and assembled quickly.

Much of this is true. The carbon argument is real: a well-managed forest sequesters carbon, and the timber harvested from it carries that stored carbon into the structure of the building. If the building stands for a hundred years, that carbon is sequestered for a hundred years. The numbers are genuinely impressive.

But the enthusiasm for timber can sometimes outrun the analysis. Timber is not infinitely renewable — it requires managed forestry, which takes decades. The fabrication of CLT is energy-intensive, and the panels must often travel long distances from factory to site. And timber buildings require more careful detailing than concrete or steel when it comes to fire, moisture, and acoustics.

I used timber in several studio projects at CMU because I believe in it — not as a silver bullet, but as part of a broader commitment to material honesty and environmental responsibility. The Hillside School I designed for Braddock uses CLT throughout; the structure is exposed, and the idea was that the children who might study there would learn, daily, what their building is made of and where it came from.

That seems, to me, like part of what architecture should do: make the relationship between building, material, and world legible to the people who inhabit it.